what is wind shear?

Question

what creates it and what does it cause?

Answer 1

Wind sheer is the difference between the speed of the wind at two very nearby locations. If you walk from behind a building into a very windy alley, you've gone through a wind shear. It causes the con trails from airplanes to be wavy and it causes the bumps when you're on an airplane.

Answer 2

What is wind shear?

Wind shear is the change in wind speed or direction with height in the atmosphere. Wind shear is important for the formation of tornadoes and hail. Some amount of wind shear is common in the atmosphere. Larger values of wind shear exist near fronts, cyclones, and the jet stream. Wind shear in an atmospheric layer that is unstable can result in clear air turbulence.

In the context of aviation, wind shear refers to the change in wind with distance along a plane's flight path. If an aircraft experiences a sudden decrease in wind speed, it can reduce the lift on its wings to dangerously low values.

Answer 3

Wind shear is the change in wind direction and/or speed with either height or on the horizontal plain. So in other words there can be horizontal wind shear and vertical wind shear.

Wind shear can be a very dangerous hazard for aviation, so warnings are issued for significant wind shear for both low levels and high levels.

There can be many reasons for wind shear. The most common is caused by the friction of the surface which causes the wind to be less near the surface than that above it (3000ft or so). That is why meteorologists often use the "gradient" level wind for forecasting. For coastal areas, overnight land breezes and afternoon seabreezes can contribute to low level wind shear. Developing frontal systems tend to slope westwards with height (the front is further west as you go higher in the atmosphere), so there is usually vertical as well as the obvious horizontal shear near them. Jet streams are a narrow band of higher level winds. They often have significant areas of vertical and horizontal shear near them and can lead to CAT (clear air turbulence) for aircraft. A strong wind normal to a mountain range can cause mountain waves which result in wind shears in the lower level. The list can go on for ever, but the important thing to know is that large wind shear can cause significant turbulence and can also help the assistance for the development of weather phenomena such as thunderstorms.

Answer 4

Variation in wind speed (speed shear) and/or direction (directional shear) over a short distance. Shear usually refers to vertical wind shear, i.e., the change in wind with height,